In the roller conveyor arts, various sorts of braking structures for conveyor rollers are known and used for the purpose of controlling roller rotation. By retarding the free rotation of a conveyor roller with a brake, the movement of loads conveyed on the conveyor rollers can be controlled and manipulated in a desirable fashion. This may be especially advantageous in environments where very heavy conveyor loads which have considerable momentum when moving even very slowly on the conveyor rollers must be manipulated in close quarters. For example, in the loading and unloading of an aircraft cargo hold heavy unitized loads often must be moved quickly and efficiently within the cargo hold with minimum risk of injury to personnel or damage to the aircraft structure.
Regarding specifically the desirable attributes of conveyor rollers in an aircraft environment, conveyor rollers may commonly be mounted in the floor of an aircraft cargo hold to support cargo loads for easy and efficient handling thereof. Of course, effective conveyor roller braking is desirable in such an environment, but in addition the attributes of compact design, highly predictable reliability, and light weight all are most desirable for an aircraft cargo hold conveyor roller brake.
The prior art has contemplated a wide variety of brake structures for conveyor rollers, for example as disclosed in the following patent documents. U.S. Pat. Nos. 4,600,093, 3,796,293, 3,713,521, 3,321,057, 2,134,373, 2,590,994, 3,918,561, 3,576,242, 3,209,880, 3,789,960, 4,000,796, 4,809,836, 3,724,642, French patent 1,461,923, Swedish patent 199,648, German patents DE 30 14 608, 2,146,020 and 1,289,779, and British patent 1,093,606.